Biology GCSE-Respiration (AQA)

Outline the flow of air from the atmosphere into our lungs starting from the nose/mouth

Nose, trachea, bronchi, bronchioles alveoli

Two structures which change the pressure inside the chest cavity to ventilate lungs

Intercostal muscles and the diaphragm

The role of the diaphragm in breathing

To contact and flatten when you inhale. This creates a vacuum effect that pulls air into the lungs. When you exhale, the diaphragm relaxes and the air is pushed out of your lungs.

The state of the diaphragm as we breathe in

Contracts and flattens

State of the diaphragm as we breathe out

Relaxes and returns to a dome shape

The function of the ribcage

Protect the heart and lungs

What happens to the ribcage as we breathe in

Ribcage moves up and out

What happens to the ribcage as we breathe out

Ribcage moves down and in

Adaptation of the lungs for effective gas exchange

Lots of alveoli to increase surface area

Rich blood supply

Extensive capillary network

Thin walls (one cell thick)

Importance of the lungs to have a rich blood supply

Maintains steep concentration gradient for effective diffusion

Aerobic Respiration

An enzyme controlled process in which glucose reacts with oxygen and energy is released. Takes place in the mitochondria of cells

Equation for aerobic Respiration

Glucose + Oxygen --> carbon dioxide + water

Type of reaction Respiration is

Exothermic

Where aerobic Respiration occurs in cells

Mitochondria

Importance of respiration

Metabolic reactions

Muscle contractions

Maintaining body temp

Active transport

1 Response of body to excersise

Increased heart rate

What happens to glycogen stored in muscles when you excersise

Converted into glucose for respiration

Anaerobic respiration

Breakdown of glucose to release small amounts of energy without oxygen

Toxic substance produced by anaerobic respiration

Lactic Acid

Oxygen debt

Amount of oxygen required to break down lactic acid

What plants make in anaerobic respiration

Ethanol and carbon dioxide

Uses of yeast in anaerobic respiration

Bread and Alcohol

Example of metabolic reaction in cells

Photosynthesis